#include<iostream>
#include<set>
#include<vector>
using namespace std;

void printSet(const set<int>& s){
        for(set<int>::const_iterator it=s.begin(); it!=s.end(); it++){
                cout<<*it<<" ";
        }
        cout<<endl;
}

int main(){

	set<int> s={1,2,3,4,5};
	for(int i=0;i<8;i+=2){
		cout<<i<<s.count(i)<<endl;
	}
	return 0;
}
